Incandescent-lamp socket.



R. M. LEVY.

INCANDESCENT lzAMP SOCKET.

APPLICATION FILED Nov.24, 1914.

1 1 90,308. Patented July 11, 1916.

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REGINALD M. LEVY, 0F NEW.YORK, N. Y.

INCANDESCENT-LAMP SOCKET.

To all whom it may concern Be-it known that I, REGINALD M. LEVY,

a citizen of Australia, and a resident of the borough of Manhattan,city, county, and State of New York, have invented certain new anduseful Improvements in Incandescent-Lamp Sockets, of which the followingis a full, clear, and exact specification.

My invention relates to incandescent electric lamp sockets and has forits object the devising of means for an expeditious way of detecting abreak in the circuit of a number .of lamps connected in series which iscaused by a defective lamp or one that is disconnected from its socket.

Referring to the drawings forming part of this specification Figure 1 isa diagrammatical view of a number of incandescent lamps connected inseries. Fig. 2 isan elevational view of an incandescent lamp and socketwith the outer casing of the socket shown'in dotted outline. Fig. 3 isan elevational view of the socket shown at right angles to Fig. 2. Fig.4 is a diagrammatical view of Fig. 2 showing themanner of connecting theconducting wires to the socket,

and Fig. 5 is a modified form of the socket.

It is a usual method in many incandescent lighting systems to connect anumber of the lamps in series and to place these in parallel with thefeed wires so that a greater potential may be used between the feedwires with a corresponding-saving in the cost of the copper usedforthewires. Often five such lamps are connected in series. In thepresent embodiment (Fig. 1) seven are shown for the purpose ofillustration only, the invention bein of course limited to no definitenumber. guch methods of arranging the lamps have the objection howeverthat when for any reason one lamp does not light, it results inpreventing all the other lamps of the particular series from lighting.When this occurs it has been necessary to examine each lamp separatelyto ascertain which of the lamps is the cause of the set not lighting.The cause may be either from a broken filament of the lamp, or a lampthat is loose in its socket, either of which results inbreaking thecircuit through the set of lamps. In inspectin ascertain the cause it isevident that if a lamp is found loose in its socket it may be tightenedto cause the necessary electrical contact and the fault therebyremedied. It

Specification of Letters Patent.

the lamps to Patented July 11,1916.

Application filed November 24, 1914. Serial No. 873,672.

is however often diflicult to ascertain a.

broken filament and the usual practice is to entirely unscrew the lampfrom the socket and replace it by another lamp. If the replacing lampcauses the series to light it is manifest that the trouble was caused bythe replaced lamp. It cannot be expected however that the first lamptried out would be the defective lamp and it often necessitates severallamps or even the entire series being replaced before the trouble islocated. This requires the expenditure of considerable time and trouble,and it is the object of this v more readily particular lamp causing theinvention to provide means for ascertaining the trouble.

The essential of my invention is to provide means for short-circuitingthe ,feed wires of each lamp so that the current may pass through theshort circuit instead of the filament constituting the lamp. As soon asthe short circuit is made in the defective lamp it is evident that thecurrent will pass through the other lamps of the entire set causing themto light thus revealing the defective lamp which may be replaced byanother lamp, thereb obviating the removal of each lamp until t etrouble has been located, as was the former practice, as has alreadybeen described. It is obvious that many mechanisms may be contrived foraccomplishing this short circuiting and in this specification I haveshown only two such .constructions.

In the drawings, 1 represents the mean-- descent lamp which is of usualconstruction and comprises the filament 2, glass bulb 3, the threadedbase 4 and the metallic terminal 5. This is insulated from the thread edbase 4 and one of the ends of the filament 2 is connected to it whilethe other end is connected to the base "I, all in the usual and wellknown way and for this reason such connections are not shown here. Thesocket 6 is incased by the usual shell 7 and comprises a body portion 8of porcelain or other nonconductlng material, and a metallic threadedsocket 9 for receiving the threaded base of the lamp in the usualmanner.

Referring more particularly to Figs. 1 to 4 inclusive, the socket isflanged inwardly and secured to the base by screws, one of which isshown at 10. The base is formed with a U-shaped channel 11 and theparticular screw shown is' extended down into ment, then through thethis channel and screwed into a binding post.

12 thereby making metallic contact with the socket. A bar 13 is securedin the porcelain base 6 and has secured to it a strip of folded metal14. The upper end of this strip is free and folded over at 15 andnormally projects upwardlyinto the path of the metal terminal 5 as itdescends downward when the lamp is screwed into the socket. The fold 15yields when in contact with the terminal 5 as the latteris being screweddownward and thereby makes a firm electrical contact therewith. Thelower end of the strip of folded metal 14: 1s folded over and is atconsiderable distance from the bar 13 to form a spring contact 16.leadwlre 17 is electrically connected to this strip of folded metal 14in any convenient manner and the other'lead wire 18 is connected to thebinding post 12. By these connections it will be evident that a circult18 formed through the filament of the lamp, that is to say, the currentpasses through the w re 17, the strip of folded metal 141, the terminal5, the side of the filament connected therewlth, and then. through thefilament to the opposite end and to the threaded base 4 which isconnected to said opposite end of the filathreaded socket 9, screw 10,binding post 12, and finally out at the wire 18. I

A turn-button 19 is provided at one side of the socket and has a shaft20 extending therefrom, through the socket and pro ecting into theU-shaped channel 11. The shaft has a cross-bar 21 secured to this endwhich preferably is placed in the same plane as the turn-button 19. Aspring contact 22 is secured to the porcelain base as by means of thescrew 23 and has a free end in the path of the bar' 21. When this bar isturned as shown at Fig. 2, that is to say, transversely to the lamp thecontact is broken between the said spring contacts 16 and 22,

and when it is turned at right angles to this position as shown in Fig.4, it crowds in between the spring contacts 16 and 17 and makes contacttherebetween, simultaneously forcing the former upwardly and the latterdownwardly to insure firm metallic contact through the three members,16, 21 and 22. A wire 24: is connected at its opposite ends to thebinding posts 12 and 22 respectively to form the short circuit when thebar 21 is turned to make the electrical contact between the contacts 16and 22.

In testing out the series of lamps shown in Fig. 1 it will only benecessary to turn the respective buttons 19 until the defective lamp isfinally reached. The current which has been interrupted by the defectexisting in the particular lamp will then flow through the correspondingwire 17, the strip of folded metal 14, the bar 21, spring terminal 22,short circuiting wire 24, binding post 12 and then out through the wire18 to the next lamp thereby producing a continuous circuit, enabling theremaining lamps to light.

Fig. 5 shows a modified construction in which 2.5 represents a bindingpost to which is connected a wire 26 for forming electrical,

contact with the terminal 5 of the lamp, one of the lead wires 27 isconnected to this binding post 25 and the other lead wire 28 isconnected to the socket 9 in the usual manner. A lever 29 is pivoted inthe porcelain base 8 by pivot pin 30. Its outer end projects beyond thelamp socket and is roflows through the wire 27, binding post 25,-

wire 32 and wire 28. This construction is convenient in instances wherethe lamps are located in the ceilings somewhat out vof reach for in suchcases all that is necessary is to use a rod as shownat 34 when tryingout the lamps of the series. The rod may be'brought under and in contactwith the head 31 and raised upwardly to tilt the lever until the shortcircuit is formed. If the lamp being tried out is not found to be thedefective one the operator lowers the rod 34 thereby releasing the leverwhich automatically returns to its normal open position. It is necessarythat the short circuit be broken in each instance before another one ismade and while this is accomplished automatically, in this embodiment itis necessary that care be taken in the previously described constructionto turn each button to break its contact before another button is turnedto make contact. For if too many short circuits are made simultaneouslyand the circuit is finally closed it is evident the potential may begreater than the lamps can withstand with attending burning out of thefuse or opening of a switch. To revent this the short circuit wires 32an 24 may be of sufficient resistance to equal that of the filamentwhich is short circuited.

Having thus described my invention I.

cally break contact when the manual control is released.

2.- In an incandescent lamp socket a pair of electrical terminalsadapted to be connected with terminals of the lamp, an electrlcalconductor permanently secured to one.

of said terminals, and manually controllable means for bringing saidconductor into electrical contact with the other terminal forshort-circuiting said terminals said means being adapted to breakcontact simultaneously with the releasing of the manual control.

3. A system of incandescent lamp sockets connected in series and meansat each socket for short-circuiting it comprising a contact member inelectrical contact with one termi nal and a lever in electrical contactwith the other terminal, said lever being adapted to make electricalcontact with the first contact member to short-circuit the terminalswhen manually controlled and to automatically break contact when themanual control is released.

This specification signed and witnessed this 2nd day of November, 1914.

REGINALD M. LEVY. Witnesses:

M. HAROLD Hoonnonr,

E. B. YEATON.

